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Atmospheric transmission algorithm for pulsed X-rays from high-altitude nuclear detonations based on scattering correction

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Nuclear Science and Techniques 2024年第3期35卷 40-52页

作者： Ding-Han Zhu xiong Zhang xiao-qiang li Peng li Yan-Bin Wang Shuang Zhang State Key Laboratory of NBC Protection for Civilian Beijing 102205China

In high-altitude nuclear detonations,the proportion of pulsed X-ray energy can exceed 70%,making it a specific monitoring signal for such *** pulsed X-rays can be captured using a satellite-borne X-ray detector following atmospheric *** quantitatively analyze the effects of different satellite detection altitudes,burst heights,and transmission angles on the physical processes of X-ray transport and energy fluence,we developed an atmospheric transmission algorithm for pulsed X-rays from high-altitude nuclear detonations based on scattering *** proposed method is an improvement over the traditional analytical method that only computes direct-transmission *** traditional analytical method exhibits a maximum relative error of 67.79% compared with the Monte Carlo *** improved method reduces this error to within 10% under the same conditions,even reaching 1% in certain ***,its computation time is 48,000 times faster than that of the Monte Carlo *** results have important theoretical significance and engineering application value for designing satellite-borne nuclear detonation pulsed X-ray detectors,inverting nuclear detonation source terms,and assessing ionospheric effects.

关键词： High-altitude nuclear detonation Atmospheric transmission Pulsed X-rays Scattering correction Analytical method Monte Carlo method

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Field experimental study on the effect of thawed depth of frozen alpine meadow soil on rill erosion by snowmelt waterflow

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International Soil and Water Conservation Research 2024年第1期12卷 54-63页

作者： Ying Zheng xiaonan Shi Fan Zhang Tingwu Lei Chen zeng xiong xiao li Wang Guanxing Wang State Key Laboratory of Tibetan Plateau Earth System Resources and Environment(TPESRE)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing100101China University of Chinese Academy of Sciences Beijing100101China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai UniversityNanjing210098China College of Water Resources and Civil Engineering China Agricultural UniversityBeijing100083China College of Geographic Science Hunan Normal UniversityChangsha410081China

Soil erosion by snow or ice melt waterflow is an important type of soil erosion in many high-altitude and high-latitude regions and is further aggravated by climate *** snowmelt waterflow erosion process is affected by soil freeze-thaws and is highly dynamically *** this study,a methodology was developed to conduct in situ field experiments to investigate the effects of the thawed depth of the frozen soil profile on snowmelt waterflow *** method was implemented on an alpine meadow soil slope at an altitude of 3700 m on the northeastern Tibetan *** erosion experiments involved five thawed soil depths of 0,10,30(35),50,and 80(100)mm under two snowmelt waterflow rates(3 and 5 L/min).When the topsoil was fully frozen or shallow-thawed(≤10 mm),its hydrothermal and structural properties caused a significant lag in the initiation of runoff and delayed soil erosion in the initial *** runoff and sediment concentration curves for fully frozen and shallow-thawed soil showed two-stage patterns characteristic of a sediment supply limited in the early stage and subject to hydrodynamic-controlled processes in the later ***,this effect did not exist where the thawed soil depth was greater than 30 *** deep-thawed cases(≥30 mm)showed normal hydrograph and sedigraph patterns similar to those of the unfrozen *** findings of this study are important for understanding the erosion rates of partially thawed soil and for improving erosion simulations in cold regions.

关键词： Snowmelt waterflow erosion Hillslope erosion process Soil freeze and thaw Runoff generation In situ experimental method

Influence of oxygen-rich hot air composite gas medium on sintering performance and function mechanism

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Journal of Iron and Steel Research International 2024年第5期31卷 1071-1081页

作者： Min Gan Hao-xiang Zheng xiao-hui Fan Zhi-yun Ji qiang li Ming Wu Yi-fan Wang xiao-long Wang Yu-feng Wu Xu-ling Chen zeng-qing Sun xiao-xian Huang School of Minerals Processing and Bioengineering Central South UniversityChangsha410083HunanChina Shanxi Taigang Stainless Steel Co. Ltd.Taiyuan030003ShanxiChina

Hot air sintering technology is used to improve the quality and production efficiency of sintered ***,the current thick layer condition highlights the disadvantage of the low oxygen potential of the hot air sintering ***,it is considered to use oxygen enrichment sintering to improve the environment of hot air *** sintering,hot air sintering,and oxygen-rich hot air sintering were compared through sintering cup experiments,and the influence of hot air and oxygen-rich hot air on sintering indexes was *** air reduced the vertical sintering velocity,while improved the yield and tumbler ***-rich hot air sintering contributed to improving the vertical sintering velocity while ensuring the quality of sintered ore,thus comprehensively improving production *** the action of hot air,the highest temperature of the sintering layer increased and the high-temperature holding time was *** oxygen enrichment,the combustion efficiency of fuels in the upper layer of materials was promoted,which optimized heat distribution in the middle and lower layers of materials and increased the content of calcium ferrite in the sintered ore,thus strengthening the sintering process.

关键词： Iron ore sintering Hot air sintering Oxygen enrichment Function mechanism

Hematochezia due to rectal invasion by an internal iliac artery aneurysm: A case report

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World Journal of Clinical Cases 2024年第11期12卷 1980-1989页

作者： Fang li Bin Zhao Yong-qiang liu Guo-Qing Chen Rong-Feng Qu Chao Xu Zhui Long Jin-Song Wu Mao xiong Wei-Hang liu li Zhu xiao-ling Feng Lei Zhang Department of General Surgery Chongqing General HospitalChongqing 401147China

BACKGROUND This case report presents the rare occurrence of hematochezia due to an internal iliac artery aneurysm leading to an arterioenteric fistula,expanding the differential diagnosis for gastrointestinal *** emphasizes the importance of considering vascular origins in cases of atypical hematochezia,particularly in the absence of common gastrointestinal causes,and highlights the role of imaging and multidisciplinary management in diagnosing and treating such unusual *** SUMMARY A 75-year-old man with a history of hypertension presented with 12 d of hematochezia,experiencing bloody stools 7-8 times per *** computed tomography(CT)scans revealed an aneurysmal rupture near the right internal iliac artery with suspected hematoma *** levels progressively decreased to 7 g/*** arterial angiography and iliac arterycovered stent placement were performed,followed by balloon *** initial stabilization,minor rectal bleeding and abdominal pain persisted,leading to further diagnostic *** identified a neoplasm and potential perforation at the proximal *** exploratory laparotomy confirmed the presence of a hematoma and an aneurysm invading the rectal wall,necessitating partial rectal resection,intestinal anastomosis,and *** recovery was successful,with no further bleeding incidents and normal follow-up CT and colonoscopy results after six *** In cases of unusual gastrointestinal bleeding,it is necessary to consider vascular causes for effective diagnosis and intervention.

关键词： Iliac artery aneurysm Hematoma Rectum Hematochezia Case report

Application of fecal immunochemical test in colorectal cancer screening:A community-based,cross-sectional study in averagerisk individuals in Hainan

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World Journal of Gastrointestinal Oncology 2024年第8期16卷 3445-3456页

作者： Fan zeng Da-Ya Zhang Shi-Ju Chen Run-Xiang Chen Chen Chen Shi-Mei Huang Da li xiao-Dong Zhang Jia-Jia Chen Cui-Yi Mo Lei Gao Jun-Tao zeng Jian-Xin xiong Zhai Chen Fei-Hu Bai Graduate School Hainan Medical UniversityHaikou 571199Hainan ProvinceChina Department of Gastroenterology Qionghai People’s HospitalQionghai 571400Hainan ProvinceChina Department of Gastroenterology Sanya Central HospitalSanya 572022Hainan ProvinceChina Department of Gastroenterology Hainan Second People’s HospitalWuzhishang 572299Hainan ProvinceChina Department of Gastroenterology Dongfang People’s HospitalDongfang 572699Hainan ProvinceChina Department of Gastroenterology The Second Affiliated Hospital of Hainan Medical UniversityHaikou 570216Hainan ProvinceChina The Gastroenterology Clinical Medical Center of Hainan Province Haikou 570216Hainan ProvinceChina

BACKGROUND The incidence of colorectal cancer(CRC)in China is steadily rising,with a high proportion of advanced-stage *** highlights the significance of early detection and prevention measures to enhance survival *** immunochemical testing(FIT)is a globally recommended CRC screening method;however,limited research has been conducted on its application in *** To assess the efficacy and adherence of FIT screening among average-risk individuals in Hainan,while also examining the risk factors associated with positive FIT *** This population-based cross-sectional study implemented FIT screening for CRC in 2000 asymptomatic participants aged 40-75 years from five cities and 21 community health centers in Hainan *** study was conducted from August 2022 to April 2023,employing a stratified sampling method to select *** with positive FIT results subsequently underwent *** predictive values for confirmed CRC and advanced adenoma were calculated,and the relationship between relevant variables and positive FIT results was analyzed usingχ2 tests and multivariate logistic *** A total of 1788 participants completed the FIT screening,with a median age of 57 years(interquartile range:40-75).Among them,503(28.1%)were males,and 1285(71.9%)were females,resulting in an 89.4%compliance rate for FIT *** overall positivity rate of FIT was 4.4%[79 out of 1788;95%confidence interval(CI):3%-5%].The specific positivity rates for Haikou,Sanya,Orient City,Qionghai City,and Wuzhishan City were 9.6%(45 of 468;95%CI:8%-11%),1.3%(6 of 445;95%CI:0.1%-3.1%),2.7%(8 of 293;95%CI:1.2%-4.3%),3.3%(9 of 276;95%CI:1.0%-6.3%),and 4.2%(11 of 406;95%CI:1.2%-7.3%),*** associations were found between age,dietary habits,and positive FIT *** of the 79 participants with positive FIT results,55 underwent colonoscopy,demonstrating an 82.2%compliance *** them,10 had a clean

关键词： Fecal immunochemical test Colorectal cancer Adenoma Screening Hainan Province

Changes in visual performance after implantation of different intraocular lenses

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International Journal of Ophthalmology(English edition) 2024年第7期17卷 1273-1282页

作者： Bo-Wen li Hao Huang Man-Sha Huang Shuang-lin Guo Lu Gao Yu-Ying zeng Lu Cheng Si-Yang Yao Jian-qiang lin lin liu Ye Yang xiao-Ming Lu Hao Cheng Department of Ophthalmology the First Affiliated Hospital of Guangzhou Medical UniversityGuangzhou Medical UniversityGuangzhou 510000Guangdong ProvinceChina Eye Center of Xiangya Hospital Hunan Key Laboratory of OphthalmologyCentral South UniversityChangsha 410008Hunan ProvinceChina Department of Ophthalmology Zhuzhou Hospital Affiliated to Xiangya School of MedicineCentral South UniversityZhuzhou 412000Hunan ProvinceChina State Key Laboratory of Ophthalmology Zhongshan Ophthalmic CenterSun Yat-sen UniversityGuangdong Provincial Key Laboratory of Ophthalmology and Visual ScienceGuangzhou 510060Guangdong ProvinceChina Department of Ophthalmology Guangzhou Red Cross HospitalJinan UniversityGuangzhou 510000Guangdong ProvinceChina AIER Eye Hospital Jinan UniversityGuangzhou 510180Guangdong ProvinceChina

AIM:To evaluate the trending visual performance of different intraocular lenses(IOLs)over time after ***:Ninety-one patients received cataract surgery with implantations of monofocal(Mon)IOLs,segmental refractive(SegRef)IOLs,diffractive(Dif)IOLs,and extendeddepth-of-focus(EDoF)IOLs were *** aberrations and optical quality collected with iTrace and OQAS within postoperative 6mo were followed and ***:Most of the visual parameters improved over the postoperative *** postoperative visual acuity(POVA)of the Mon IOL,SegRef IOL,and EDoF IOL groups achieved relative stability in earlier states compared with the Dif IOL ***,the overall visual performance of the 3 IOLs continued to upturn in small extents within the postoperative *** optical quality initially improved in the EDoF IOL group,then in the Mon IOL,SegRef IOL,and Dif IOL *** and objective visual performance of the Mon IOL and EDoF IOL groups,as well as POVA and visual quality of the Dif IOL group,improved in the postoperative 1mo and *** the postoperative 6mo,gradual improvements were observed in the visual acuity and objective visual performance of the SegRef IOL group,as well as in the postoperative optical quality of the Dif IOL ***:The visual performance is different among eyes implanted with different *** findings of the current study provide a potential reference for ophthalmologists to choose suitable IOLs for cataract patients in a personalized solution.

关键词： intraocular lenses visual performance changing characteristics high-order wavefront aberration

GATIS score for predicting the prognosis of rectal neuroendocrine neoplasms:A Chinese multicenter study of 12-year experience

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World Journal of Gastroenterology 2024年第28期30卷 3403-3417页

作者： Xin-Yu zeng Ming Zhong Guo-Le lin Cheng-Guo li Wei-Zhong Jiang Wei Zhang li-Jian Xia Mao-Jun Di Hong-Xue Wu xiao-Feng liao Yue-Ming Sun Min-Hao Yu Kai-xiong Tao Yong li Rui Zhang Peng Zhang Department of Gastrointestinal Surgery Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430074Hubei ProvinceChina Department of Gastrointestinal Surgery Renji HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200127China Department of General Surgery Peking Union Medical College HospitalPeking Union Medical CollegeBeijing 100730China Department of Colorectal Surgery Fujian Medical UniversityFuzhou 350401Fujian ProvinceChina Department of Colorectal Surgery Changhai HospitalShanghai 200433China Department of Gastrointestinal Surgery The First Affiliated Hospital of Shandong First Medical UniversityJinan 250118Shandong ProvinceChina Department of Gastrointestinal Surgery Taihe HospitalHubei University of MedicineShiyan 442099Hubei ProvinceChina Department of Gastrointestinal Surgery I Section Renmin Hospital of Wuhan UniversityWuhan 430060Hubei ProvinceChina Department of General Surgery Xiangyang Central HospitalAffiliated Hospital of Hubei University of Arts and ScienceXiangyang 441021Hubei ProvinceChina Department of Colorectal Surgery Jiangsu Province HospitalNanjing Medical UniversityNanjing 210029Jiangsu ProvinceChina Department of Gastrointestinal Surgery School of MedicineShanghai Jiao Tong UniversityShanghai 200127China Department of General Surgery Guangdong Provincial People’s HospitalGuangdong Academy of Medical SciencesGuangzhou 510080Guangdong ProvinceChina Department of Colorectal Surgery Liaoning Cancer HospitalShenyang 110042Liaoning ProvinceChina

BACKGROUND There is currently a shortage of accurate,efficient,and precise predictive instruments for rectal neuroendocrine neoplasms(NENs).AIM To develop a predictive model for individuals with rectal NENs(R-NENs)using data from a large *** Data from patients with primary R-NENs were retrospectively collected from 17 large-scale referral medical centers in *** forest and Cox proportional hazard models were used to identify the risk factors for overall survival and progression-free survival,and two nomograms were *** A total of 1408 patients with R-NENs were *** grade,T stage,tumor size,age,and a prognostic nutritional index were important risk factors for *** GATIS score was calculated based on these five *** overall survival prediction,the respective C-indexes in the training set were 0.915(95%confidence interval:0.866-0.964)for overall survival prediction and 0.908(95%confidence interval:0.872-0.944)for progression-free survival *** to decision curve analysis,net benefit of the GATIS score was higher than that of a single *** time-dependent area under the receiver operating characteristic curve showed that the predictive power of the GATIS score was higher than that of the TNM stage and pathological grade at all time *** The GATIS score had a good predictive effect on the prognosis of patients with R-NENs,with efficacy superior to that of the World Health Organization grade and TNM stage.

关键词： Rectal neuroendocrine neoplasm Nomogram Random forest Prognosis Overall survival Progression-free survival

Development and validation of a nomogram based on perioperative risk factors for the prediction of early thrombotic complications following pediatric liver transplantation

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中华医学杂志(英文版) 2024年第16期137卷 1993-1995页

作者： You qiang Qu Enze zeng Kaining liu Jianrong Yang Qing Tang Hui Feng xiao Yao Jia Huang Xinru Zhang Tong Fu Binsheng li Hua Zhao Hui Zheng Jun Yi Shuhong Yang Yang Department of Hepatic Surgery and liver Transplantation Center of the Third Affiliated Hospital of Sun Yat-sen University Organ Transplantation Research Center of Guangdong Province Guangdong Province Engineering Laboratory for Transplantation Medicine Guangzhou Guangdong China Guangdong Key Laboratory of liver Disease Research Key Laboratory of Liver Disease Biotherapy and Translational Medicine of Guangdong Higher Education Institutes The Third Affiliated Hospital of Sun Yat-sen University Guangzhou Guangdong China Department of Ultrasound The Third Affiliated Hospital of Sun Yat-Sen University Guangzhou Guangdong China Surgical ICU of the Third Affiliated Hospital of Sun Yat-sen University Guangzhou Guangdong China

Optimized online filter stack spectrometer for ultrashort X-ray pulses

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Nuclear Science and Techniques 2024年第5期35卷 85-98页

作者： Jia-Xing Wen Ge Ma Ming-Hai Yu Yu-Chi Wu Yong-Hong Yan Shao-Yi Wang Huai-Zhong Gao Lu-Shan Wang Yu-Gang Zhou qiang li Yue Yang Fang Tan xiao-Hui Zhang Jie Zhang Wen-Bo Mo Jing-Qin Su Wei-Min Zhou Yu-Qiu Gu Ming zeng Zong-Qing Zhao Science and Technology on Plasma Physics Laboratory Laser Fusion Research CenterCAEPMianyang 621900China Department of Engineering Physics Tsinghua UniversityBeijing 100084China Key Laboratory of Particle and Radiation Imaging(Tsinghua University) Ministry of EducationBeijing 100084China School of Information Engineering Southwest University of Science and TechnologyMianyang 621010China

Currently,with the advent of high-repetition-rate laser-plasma experiments,the demand for online diagnosis for the X-ray spectrum is increasing because the laser-plasma-generated X-ray spectrum is very important for characterizing electron dynamics and *** this study,scintillators and silicon PIN(P-type–intrinsic-N-type semiconductor)diodes were used to construct a wideband online filter stack *** X-ray sensor and filter arrangement was optimized using a genetic algorithm to minimize the condition number of the response ***,the unfolding error was significantly reduced based on numerical *** detector responses were quantitatively calibrated by irradiating the scintillator and PIN diode with various nuclides and comparing the measuredγ-ray peaks.A prototype 15-channel spectrometer was developed by integrating an X-ray detector with front-and back-end *** prototype spectrometer could record X-ray pulse signals at a repetition rate of 1 ***,an optimized spectrometer was employed to record the real-time spectra of laser-driven bremsstrahlung *** optimized spectrometer offers a compact solution for spectrum diagnostics of ultrashort X-ray pulses,exhibiting improved accuracy in terms of spectrum measurements and repetition rates,and could be widely used in next-generation high-repetition-rate high-power laser facilities.

关键词： Filter stack spectrometer Laser plasma diagnostics X-ray diagnostics Scintillator PIN diode

维普期刊数据库